Wednesday, August 11, 2010

Resveratrol-Rich Plant Extract Stifles Inflammation in Humans

Resveratrol’s antioxidant and anti-inflammation actions shown previously only in vitro and in laboratory animals have now been observed in a small human study.

State University of Buffalo New York and Kaleida Health researchers found that supplementation with a plant extract containing resveratrol suppressed generation of free radicals called reactive oxygen species (ROS) and reduced expression of two major proinflammatory pathways.

Writing in their study, published in Journal of Clinical Endocrinology and Metabolism, the researchers state that they have demonstrated for the first time in humans “comprehensive effects on ROS generation and inflammation” and the “antiaging action of resveratrol.”

In the trial, two groups of 10 healthy adults were randomized to receive placebo or 200 milligrams of Japanese knotweed extract (Polygonum cuspidatum) supplying 40 milligrams of resveratrol daily. Fasting blood samples were collected before, during and after six weeks of supplementation. Subjects chosen were not on any antiinflammatory drugs.

The researchers’ data showed clear suppression of ROS generation and reduced expression of TNF-alpha and IL-6, which are regulated by NFkB, that led to falling levels of C-reactive protein, which are all involved with inflammatory response.

In parallel, the extract reduced expression of two major proinflammatory enzymes, JNK-1 and IKK-beta.

Resveratrol’s effects on reducing oxidative stress and inflammation are thought to take place because it activates production of SIRT1, one of a family of proteins that is positively associated with influencing fat metabolism, slowing aging, and extending lifespan in response to calorie restriction and fasting in yeast and animals.

Chronic oxidative stress and inflammation are implicated as factors that accelerate aging because of damage caused to cellular components including membranes, mitochondria and DNA.